It is often necessary to place a spot of a functional material onto a surface for use as a sensor to detect and measure a condition (e.g., temperature, pressure, RH, pH, concentration of a target analyte such as O2, O3, CO2, CO, etc) within a confined space (e.g., a carbonated beverage bottle, a food container, a Petri dish, a sealed shipping container, etc.). Due to the expense of most functional materials, it is generally desirable to employ as little functional material as necessary, often resulting in a spot that is less than 100 mm2, typically less than 25 mm2 and often less than 10 mm2.
Handling of such small elements is difficult, especially when direct contact with the functional material is to be avoided in an effort to avoid contaminating or damaging the functional material.
Accordingly, a substantial need exists for an inexpensive source of functional material sensors that is easily manufactured, easily handled and easily applied.